Re: "Projector of the Sharpest Beam of Electric Waves"
Are you referring to the two-volume set by Collin a d Zucker?
Thanks.
DaveD
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Show quoted text
On Mar 14, 2021, at 13:10, Sean Turner < [email protected]> wrote: The most absolutely mathematically rigorous book(s) about antennas I know of are R.E. Collin's "Antenna Theory", volumes 1 & 2. Mine are in my office at work or I'd look to see how he treats this topic. Be ready though, Collin pulls zero punches when it comes to math.
Sean
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Re: "Projector of the Sharpest Beam of Electric Waves"
The most absolutely mathematically rigorous book(s) about antennas I know of are R.E. Collin's "Antenna Theory", volumes 1 & 2. Mine are in my office at work or I'd look to see how he treats this topic. Be ready though, Collin pulls zero punches when it comes to math.
Sean
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Re: "Projector of the Sharpest Beam of Electric Waves"
The Gnu development tool suite is of very high quality. It includes FORTRAN 77, 95, C, C++, Objective C and possibly some others for a wide range of machine architectures and operating systems.
http://gcc.gnu.org/releases.html
Octave is a very good Matlab clone. I know that Octave is supported on Windows, Linux and FreeBSD. Very likely the Gnu development tools are supported on Windows, but I only use Windows for binary only software.
https://www.gnu.org/software/octave/index
Have Fun!
Reg
On Sunday, March 14, 2021, 09:28:31 AM CDT, jafinch78 . <jafinch78@...> wrote:
I thought there were free Fortran compilers available last I looked into (two decades back).? For some reason, I first was thinking a free Visual Studio version may allow importing and compiling, though I haven't verified.?
A quick Google search of "" returned far more results than I expected.? Worth reading into if you're interested in.? Nice to see a range of options.?
I was also pleasantly surprised to find a MATLAB code to Python compatible code translator appears.?
, where the compiler was in a shady transition from not able to convert to C code and requiring the MATLAB Component Runtime (MCR) for the MATLAB Compiled apps.?
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Re: "Projector of the Sharpest Beam of Electric Waves"
The 4th ed of Ballanis has an extensive derivation via the method of moments. However, that is an approximation, so it is not an avenue to a proof. Lawson's ARRL monograph goes into much detail, but again is of an applied mathematics vein and relies on approximations.
I feel certain that a proof must be via the Fourier transform. Having met a gentleman who was performing FFTs via a desk calculator and trig tables in the 1950's long before the famous paper by Cooley and Tukey, I have great appreciation for practical insight and superposition. The pictorial dictionary of transform pairs in Bracewell's book are invaluable for acquiring such insight.
I should not at all be surprised if Uda had a grasp of the Fourier transform such that he could visualize where the optimum solution lay and then simply used empirical experiment to adjust for fringe effects. The fact that Uda referred to it as a "wave canal" lends some support for this hypothesis.
My copy of Bracewell is MIA at the moment which is not surprising as it is my most heavily used mathematics text. Neither Churchill's "Operational Mathematics" nor Papoulis' excellent text on the Fourier transform stray far enough from the pure mathematics to offer any insight.
Uda's phrase, "wave canal" suggests that an analysis in terms of a transmission line might yield a rigorous proof of the assertion of "sharpest".
A transmission line constructed in the form of uniformly spaced dipoles might give further insight and 2-6 GHz is relatively low frequency today. Light gauge wire and heavy fishline might produce some very interesting results. I only wish I had my lab set up to do that instead of just a pile of equipment on mover's dollies.
At the moment my research workstation is sitting on the bench as I try to track down a bit fade problem :-(
Have Fun!
Reg On Saturday, March 13, 2021, 10:21:39 PM CST, Dave Daniel <kc0wjn@...> wrote:
I also read the reproduction of the Yagi-Uda paper in QEX and was also
struck by the lack of any sort of mathematical basis for the development
of the antenna.
There is also another paper that appears in the PROCEEDINGS OF THE IEEE,
VOL. 85, NO. 11, NOVEMBER 1997 by David Pozar entitled "Beam
Transmission of Ultra Short Waves: An Introduction to the Classic Paper
by H. Yagi" which elaborates somewhat on the Yagi-Uda antenna. As nearly
as I can tell, the original development was accomplished in a strictly
empirical manner.
Looking through my antenna books, I find that there is quite a lot of
mathematical infromation in Balanis' "Antenna Theory", 3rd Edition. The
information appears to be spread throughout the text. Section 10.3.3,
starting on page 577, contains (eventually) a rather involved
theoretical analysis of the antenna using the integral equation moment
method followed by a description of how to calculate the antenna's far
field pattern.
There are also apparently? MatLab and FORTRAN programs on the CD that
was included in the book. Unfortunately, I no longer have access to
FORTRAN compilers or MatLab.
Weeks' "Antenna Engineering", Section 4.7.3, page 196 has a simpler
description which shows how to calculate the antenna element currents
and the resulting radiation pattern.
Oddly, I do not see any mention of Yagi-Uda arrays in either of the
first two editions of Kraus' "Antennas" but I do find a bit of
descriptive information in the third edition, Section 8.6, page 246.
Finally Elliot's "Antenna Theory and Design, Revised Edition, IEEE
Press, has two sections on Yagi-Uda arrays: Section 8.7, page 368,
describes two-element antennas and Section 8.8, page 373, describes
antennas with three or more elements.
I hope that helps.
DaveD
On 3/13/2021 8:47 PM, Reginald Beardsley via groups.io wrote:
> My copy of QEX came today and I was immediately drawn to the famous paper by Yagi & Uda.
>
> Though not meant in any way as a criticism, I had hoped for more mathematical rigor.? I don't know if that was presented in another paper as mention is made that more was forthcoming.? Does anyone know?
>
> I don't recall ever seeing a Fourier analysis of the Yagi-Uda design.? Ronald Bracewell discusses many interesting arrays, but at least to my recollection, only covered slotted RF arrays in the 2nd edition.? Seismic style point receivers are well treated, but point receivers are trivially simple.? At least to me.? But that may simply reflect a career spent on elastic waves instead of electromagnetic? waves.? It's the same wave equation, but the devil is in the details so I get very nervous when I switch the physical domain.
>
> The title of the paper should be mathematically provable.? I'm interested, but a bit too busy and too lazy to do the analysis required for a proof.? Which completely neglects whether I still have the skills for such an undertaking.? Math was never my strong suite and it has been far too many years.
>
> If anyone knows of a rigorous proof that the Yagi-Uda is the "sharpest beam" I am *very* interested in reading it.? On inspection it seems plausible, but mathematics at that level is rather a black art to mere applied math people like me.
>
> Thanks and..
>
> Have Fun!
> Reg
>
>
>
>
>
--
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|
Re: "Projector of the Sharpest Beam of Electric Waves"
Which edition of Kraus (there are three)?
Thanks.
DaveD
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Show quoted text
On Mar 14, 2021, at 11:15, James Amos < jimamos@...> wrote: The article is a? reprint of the original paper that was published in 1926.??I think the point of the original article was to show discovery of this type of antenna.? ? Of course, the general theory of antennas was not what it would be come yet either in 1926.? ?Today, they would have written the paper, and immediately filed a patent.? ?I didn't see any evidence of a patent from them though.
I found that Kraus does discuss this antenna type on Chapter 11, page 320 as a three element linear array.? He references a later paper by Yagi, but not the original.? ?There is no general theoretical treatment of the antenna type, though he does point to a couple of other references that discuss a single reflector.? He goes into dipoles to a great extent in an earlier chapter,? which is still the driven element for a Yagi.?
73's
Jim? N8CAH
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Re: "Projector of the Sharpest Beam of Electric Waves"
The article is a? reprint of the original paper that was published in 1926.??I think the point of the original article was to show discovery of this type of antenna.? ? Of course, the general theory of antennas was not what it would be come yet either in 1926.? ?Today, they would have written the paper, and immediately filed a patent.? ?I didn't see any evidence of a patent from them though.
I found that Kraus does discuss this antenna type on Chapter 11, page 320 as a three element linear array.? He references a later paper by Yagi, but not the original.? ?There is no general theoretical treatment of the antenna type, though he does point to a couple of other references that discuss a single reflector.? He goes into dipoles to a great extent in an earlier chapter,? which is still the driven element for a Yagi.?
73's
Jim? N8CAH
|
Re: "Projector of the Sharpest Beam of Electric Waves"
For some time I have wanted to start using Gnu Octave. The last
time I looked, the authors of that code considered any differences
between MatLab and Octave to be a bug in Octave. It appears that
Octave now has a wide variety of packages which support various
computational methods, similar to MatLab's Toolboxes. I did not
see an Octave package for PDEs, though.
At one time the MathWorks would sell one a copy of MatLab,
Simulink and whatever toolboxes one wished to purchase for a
fraction of the commercial cost if one signed an agreement that
precluded the commercial use of that copy of MatLab. I did this in
2000; when I went to re-up, The MathWorks informed me that they no
longer supported that option. Later on, I believe they expanded
the capabilities of the student version of MatLab. I briefly
pursued the use of that but did not explore it in depth.
You are correct that are are various free FORTAN compilers
available online. I have not written FORTRAN code since the early-
to mid-eighties.
DaveD
On 3/14/2021 12:16 AM, jafinch78 .
wrote:
I thought there
were free Fortran compilers available last I looked into (two
decades back).? For some reason, I first was thinking a free
Visual Studio version may allow importing and compiling, though I
haven't verified.?
A quick Google search of "" returned far more results than I expected.?
Worth reading into if you're interested in.? Nice to see a range
of options.?
I was also pleasantly surprised to find a MATLAB code to Python
compatible code translator appears.?
, where the compiler
was in a shady transition from not able to convert to C code and
requiring the MATLAB Component Runtime (MCR) for the MATLAB
Compiled apps.?
|
Re: "Projector of the Sharpest Beam of Electric Waves"
The OMPC referenced download links at?http://ompc.juricap.com/download, from bitbucket, are broken. Though found a github repository for OMPC: ?
Haven't tested since I don't have a Python 2.5 legacy, circa 2008'ish, machine built at the time being.? Figured share however.?
In regards to the Yagi-Uda antenna designs, wondering what the inductive logic is regarding the range of phenomena characteristics, i.e. internal, boundary and external conditions.? Even experimenting to deduce, would be a very interesting project to determine the mathematical observations that characterize the design performance.??
|
Re: "Projector of the Sharpest Beam of Electric Waves"
I thought there were free Fortran compilers available last I looked into (two decades back).? For some reason, I first was thinking a free Visual Studio version may allow importing and compiling, though I haven't verified.?
A quick Google search of "" returned far more results than I expected.? Worth reading into if you're interested in.? Nice to see a range of options.?
I was also pleasantly surprised to find a MATLAB code to Python compatible code translator appears.?
, where the compiler was in a shady transition from not able to convert to C code and requiring the MATLAB Component Runtime (MCR) for the MATLAB Compiled apps.?
|
Re: "Projector of the Sharpest Beam of Electric Waves"
I also read the reproduction of the Yagi-Uda paper in QEX and was also struck by the lack of any sort of mathematical basis for the development of the antenna.
There is also another paper that appears in the PROCEEDINGS OF THE IEEE, VOL. 85, NO. 11, NOVEMBER 1997 by David Pozar entitled "Beam Transmission of Ultra Short Waves: An Introduction to the Classic Paper by H. Yagi" which elaborates somewhat on the Yagi-Uda antenna. As nearly as I can tell, the original development was accomplished in a strictly empirical manner.
Looking through my antenna books, I find that there is quite a lot of mathematical infromation in Balanis' "Antenna Theory", 3rd Edition. The information appears to be spread throughout the text. Section 10.3.3, starting on page 577, contains (eventually) a rather involved theoretical analysis of the antenna using the integral equation moment method followed by a description of how to calculate the antenna's far field pattern.
There are also apparently? MatLab and FORTRAN programs on the CD that was included in the book. Unfortunately, I no longer have access to FORTRAN compilers or MatLab.
Weeks' "Antenna Engineering", Section 4.7.3, page 196 has a simpler description which shows how to calculate the antenna element currents and the resulting radiation pattern.
Oddly, I do not see any mention of Yagi-Uda arrays in either of the first two editions of Kraus' "Antennas" but I do find a bit of descriptive information in the third edition, Section 8.6, page 246.
Finally Elliot's "Antenna Theory and Design, Revised Edition, IEEE Press, has two sections on Yagi-Uda arrays: Section 8.7, page 368, describes two-element antennas and Section 8.8, page 373, describes antennas with three or more elements.
I hope that helps.
DaveD
toggle quoted message
Show quoted text
On 3/13/2021 8:47 PM, Reginald Beardsley via groups.io wrote: My copy of QEX came today and I was immediately drawn to the famous paper by Yagi & Uda.
Though not meant in any way as a criticism, I had hoped for more mathematical rigor. I don't know if that was presented in another paper as mention is made that more was forthcoming. Does anyone know?
I don't recall ever seeing a Fourier analysis of the Yagi-Uda design. Ronald Bracewell discusses many interesting arrays, but at least to my recollection, only covered slotted RF arrays in the 2nd edition. Seismic style point receivers are well treated, but point receivers are trivially simple. At least to me. But that may simply reflect a career spent on elastic waves instead of electromagnetic waves. It's the same wave equation, but the devil is in the details so I get very nervous when I switch the physical domain.
The title of the paper should be mathematically provable. I'm interested, but a bit too busy and too lazy to do the analysis required for a proof. Which completely neglects whether I still have the skills for such an undertaking. Math was never my strong suite and it has been far too many years.
If anyone knows of a rigorous proof that the Yagi-Uda is the "sharpest beam" I am *very* interested in reading it. On inspection it seems plausible, but mathematics at that level is rather a black art to mere applied math people like me.
Thanks and..
Have Fun!
Reg
--
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|
How do we build advertising revenue for QEX?
Including covers, the current issue is 30 pages. There are 5 ads, one of which is ARRL and doesn't count.
Confronted by the removal of technical articles from QST, I requested that QEX be an available choice for member print publications. I am happy to say that was approved, though it has not appeared in any of the renewal forms yet.
I care far more about the technology of radio than I do about operating. "Wall paper" just never appealed to me. QEX is important to me. So how do we make it thrive?
The only way I can think of is to have more content over a diverse range of levels from the uber techno wonk of my Yagi-Uda post to simple stuff suited to, "I just bought a kit on ebay."
I must put myself first in line for the dock in the latter case. Most of the older QRP designs have output filters which do not meet the currently mandated standards. Despite that, they are being sold on ebay to novices who have neither the knowledge nor the test kit to determine that they are illegal. I did a bunch of work on the Chinese kits for the Pixie 2 designed by WA6BOY and posted it to EEVblog.
I contacted Kaz to see if that level of topic would be acceptable, but never got around to writing an article. I shall correct that omission shortly.
The sad fact of the matter is if the current readers of QEX do not help generate new readers and revenue, QEX will fade away and ham radio will drift even farther in the appliance direction.
Almost everything important to modern radio was developed by amateurs. Admittedly, many were professional electronics engineers, but it was what they did on their own time with their own money that made the technology we enjoy today. They cared enough to try what management would not fund.
What won't be developed because amateurs don't try it?
Reg
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"Projector of the Sharpest Beam of Electric Waves"
My copy of QEX came today and I was immediately drawn to the famous paper by Yagi & Uda.
Though not meant in any way as a criticism, I had hoped for more mathematical rigor. I don't know if that was presented in another paper as mention is made that more was forthcoming. Does anyone know?
I don't recall ever seeing a Fourier analysis of the Yagi-Uda design. Ronald Bracewell discusses many interesting arrays, but at least to my recollection, only covered slotted RF arrays in the 2nd edition. Seismic style point receivers are well treated, but point receivers are trivially simple. At least to me. But that may simply reflect a career spent on elastic waves instead of electromagnetic waves. It's the same wave equation, but the devil is in the details so I get very nervous when I switch the physical domain.
The title of the paper should be mathematically provable. I'm interested, but a bit too busy and too lazy to do the analysis required for a proof. Which completely neglects whether I still have the skills for such an undertaking. Math was never my strong suite and it has been far too many years.
If anyone knows of a rigorous proof that the Yagi-Uda is the "sharpest beam" I am *very* interested in reading it. On inspection it seems plausible, but mathematics at that level is rather a black art to mere applied math people like me.
Thanks and..
Have Fun!
Reg
|
TDS784C 4ch Color 1 GHz Oscilloscope For Sale - Fully Working
I need to make some space on my bench, and for measurements as high as this will go, I usually move to a spectrum analyzer anyway. 4 channels, 1 GHz, color display. GPIB and floppy work; I didn't test serial or Centronics but those rarely fail. All four channels work. Likely out of "official" calibration, but everything looks good by comparing to my other equipment. Includes the deep memory 8 meg option. A bit of sticker residue where someone before me peeled off a sticker or two, top left corner of the face and along the top edge of the front bezel. Seal "calibration void if broken" sticker still intact. Power cord included but no probes or other cables. Missing left rear foot.
I'm asking $500 here (and on other fora that you may be subscribed to) plus shipping, if you can't do local pickup. I'm in northeast Ohio, USA, more specifically about halfway between Cleveland and Akron. I'd prefer local pickup, will even drive a reasonable distance to meet you. Shipping weight will be about 35# (16 KG).
Steve Hendrix
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File /ReducingImdInHigh-levelMixers_QEX_2001_05,06.pdf uploaded
#file-notice
The following files have been uploaded to
the Files area of the [email protected] group.
By: Daniel Ricardo Perez
|
Re: Frequencies to be terminated at DBM output
Daniel,
Unfortunately, your links did not work this morning.
I recently developed an interest in IMD and bought a copy of:
Intermodulation Distortion in Microwave and Wireless Circuits
J.C. Pedro & N.B. Carvalho
Artech House 2003
That was the only monograph I could find on the topic. I have not spent a lot of time with it, but it looks quite thorough. It's a serious math book, but well illustrated with abundant figures comparing calculated and measured values for a variety of circuit topologies.
Much of the discussion is in terms of Volterra functions which I'd not heard of. But it's a basically a power or Taylor series expansion of ODEs. So to solve an Nth order Volterra series you have to solve N ODEs.
I've attached scans of a few pages which look as if they might be helpful. However, as I don't know the material I can't say if they include enough to be useful. In such matters what you already know is a major factor in what you can understand.
Have Fun!
Reg
NB My current focus is metal casting and similar pursuits, so it will be a while before I dig into this myself. At present I'm trying to set up to melt steel and iron.
On Saturday, January 2, 2021, 07:01:21 AM CST, Daniel Ricardo Perez via groups.io <danyperez1@...> wrote:
Hello group! Happy new year to all!
In PA3CJD's site??there's a good compilation of articles from QEX and QST:
? ?-> Technic -> Electronics -> Radio Tech -> Radio Amateur Magazines
I am specially interested in this:
? ?
Here he makes several IMD tests on a DBM, with matched and mismatched impedances both at the IF and RF ports. I was surprised that RF port matching has an important impact.
After reading this and other similar articles, there's a point that remains unclear for me: what are the specific frequencies that really demand having proper termination? RF+LO if I use RF-LO (or vice versa)? The LO feedthrough? Whatever?
Suppose I want to receive 7.00MHz, and there are strong undesired signals at 7.01 and 7.02. 3rd order IMD within the DBM will fabricate a fake 7.00 IF even with a resistive 50 ohm load.
Now, I place a diplexer after the DBM, and a xtal filter after the diplexer. The diplexer is much wider than the filter, so the DBM will still see a capricious Z at frequencies so close as 10 and 20kHz away from the desired IF, so I thought these ones would reflect back into the DBM, mix again, and worsen the overall IMD. But I must be wrong because if this was true then a diplexer would be useless.
Can anybody explain the IMD worsening mechanism?
Thank you!
Daniel Perez LW1ECP
|
Frequencies to be terminated at DBM output
Hello group! Happy new year to all!
In PA3CJD's site??there's a good compilation of articles from QEX and QST:
? ?-> Technic -> Electronics -> Radio Tech -> Radio Amateur Magazines
I am specially interested in this:
? ?
Here he makes several IMD tests on a DBM, with matched and mismatched impedances both at the IF and RF ports. I was surprised that RF port matching has an important impact.
After reading this and other similar articles, there's a point that remains unclear for me: what are the specific frequencies that really demand having proper termination? RF+LO if I use RF-LO (or vice versa)? The LO feedthrough? Whatever?
Suppose I want to receive 7.00MHz, and there are strong undesired signals at 7.01 and 7.02. 3rd order IMD within the DBM will fabricate a fake 7.00 IF even with a resistive 50 ohm load.
Now, I place a diplexer after the DBM, and a xtal filter after the diplexer. The diplexer is much wider than the filter, so the DBM will still see a capricious Z at frequencies so close as 10 and 20kHz away from the desired IF, so I thought these ones would reflect back into the DBM, mix again, and worsen the overall IMD. But I must be wrong because if this was true then a diplexer would be useless.
Can anybody explain the IMD worsening mechanism?
Thank you!
Daniel Perez LW1ECP
|
I have depressingly little knowledge of the subject. Just a general notion and a bunch of time playing around with an HP 8560A w/ TG and some 10 cent crystals. To the best of my recollection, the notch when sweeping a crystal exceeded the dynamic range of my 8560A. That suggests to me that attention to shielding will pay off. Harke, I'm not familiar with the work you cited. Would you please provide a link? I'd like to urge you to do some experiments with various shielding arrangements and report them here. Aside from providing a forum to discuss QEX articles, I'd like to see this turn into a springboard that encourages people to write for QEX. So I'd be super happy if your posts here led to a QEX article. At the moment I'm in "metal work mode" melting tin, lead, aluminum and copper scrap into ingots for later use. For anyone interested in that check out [email protected]. At present I'm researching the transition from 1-3 lbs of metal to 10-30 lbs per melt. I've got an 8753B and 85046A test set, so I can replicate your work, subject to my learning to operate the beast. Spinning up my 8510C is rather more difficult as it's a complete set of parts bought one piece at a time and might or might not work. I have not played guitar in several months, so likely after metal mangling for a while I'll go through several months of guitar before I roll back around to serious mucking about with electronics. Have Fun! Reg On Friday, January 1, 2021, 08:43:15 AM CST, Harke Smits via groups.io <yrrah53@...> wrote:
Hello Group,
There is a good deal of crystal knowledge here so I thought to ask this group.
I am working on a crystal notch filter at 14 MHz for NPR measurements. Notch would be ideally about 1-2 kHz wide and 100 dB deep.? I have seen designs by OE3HKL and W7ZOI, which is, as far as I can see, just about all that is published in amateur literature. Others refer to these publications. Basically the design comes down to an LC low pass filter with crystals at the nodes to ground. I follow that approach as well. I have transformers (1:9) at the input and calculated a Chebyshev LPF at 22 MHz with 400 ohm impedance. A series L as input and output, 4 L's in total. Each node has a crystal to ground, actually 5, so also directly at the transformers. These crystals merely make a short to ground. The LPF works as expected with a little more insertion loss, likely caused by the not ideal RF transformers. Construction is "Manhattan" style, the input and output connectors are separated by about 10 cm. My first results were less than satisfactory so then I tried pulling the crystals with a series trimcap. I have not seen this before but now I am able to control the notch much better. This of course lowers the Q somewhat. On my vna (HP8753C) I can trim a notch of about 1 kHz wide and 60 dB deep. I am wondering if this has been done before and if a better construction with screening would effectively give me about 100 dB isolation. I guess yes but I am curious to learn from others. Or would I need more sections? In the end, if I have a fair chance of success, I will built a better screened version, of course.
Any advise welcome. Best 73 de
Harke, PA0HRK
|
Hello Group,
There is a good deal of crystal knowledge here so I thought to ask this group.
I am working on a crystal notch filter at 14 MHz for NPR measurements. Notch would be ideally about 1-2 kHz wide and 100 dB deep.? I have seen designs by OE3HKL and W7ZOI, which is, as far as I can see, just about all that is published in amateur literature. Others refer to these publications. Basically the design comes down to an LC low pass filter with crystals at the nodes to ground. I follow that approach as well. I have transformers (1:9) at the input and calculated a Chebyshev LPF at 22 MHz with 400 ohm impedance. A series L as input and output, 4 L's in total. Each node has a crystal to ground, actually 5, so also directly at the transformers. These crystals merely make a short to ground. The LPF works as expected with a little more insertion loss, likely caused by the not ideal RF transformers. Construction is "Manhattan" style, the input and output connectors are separated by about 10 cm. My first results were less than satisfactory so then I tried pulling the crystals with a series trimcap. I have not seen this before but now I am able to control the notch much better. This of course lowers the Q somewhat. On my vna (HP8753C) I can trim a notch of about 1 kHz wide and 60 dB deep. I am wondering if this has been done before and if a better construction with screening would effectively give me about 100 dB isolation. I guess yes but I am curious to learn from others. Or would I need more sections? In the end, if I have a fair chance of success, I will built a better screened version, of course.
Any advise welcome. Best 73 de
Harke, PA0HRK
|
Re: Help with old function generator
Cory, similar to many function generators of the era,
Search the heathkit, Exact, Wavetek in 1970-1990
This one seems like a copy of one of those.
The pulse TTL, TTL logic levels, low sinks a few mA, high 3V CMOS 0, 5V
Check a wiki for logic families
Sweep
lin- freq increasing at fixed hZ per unit time, Log, logarithmic increasing freq with time.
Similar to spectrum or network analyzer sweep
Counter is off in some control settings.
Just play around
Jon
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Help with old function generator
Hi all
I inherited an old function generator (Tristat Electronics FGC001) from another ham (W7OSP SK). I know enough to be able to use it, but I have no idea what some of the knobs on here do. I can't find a manual (or any specs) for this particular model online. Does anyone know what these knobs do or can someone direct me to a manual?
The controls I'm wondering about are:
Sweep: Lin/Log and Ext/Int (1st and 2nd knobs from the left)
Pulse: TTL -> CMOS (4th knob from the left)
Also I don't know how to work the frequency counter, which would be nice to have.
Thanks
Cory
KG7BBV
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jafinch78 .
Daniel Ricardo Perez LW1ECP
Froggie the Gremlin
